2. javascript map.js

const nums = [1, 2, 3, 4, 5, 6, 7, 8, 9];

function double(num) {
    return num * 2;
}

const doubleNums = nums.map(double);
console.log(doubleNums)
\\ [2, 4, 6, 8, 10, 12, 14, 16, 18]
const doubleNums2 = nums.map(number => number * 2);
console.log(doubleNums2)
\\ [2, 4, 6, 8, 10, 12, 14, 16, 18]